(Railroad) Columbia Bridge Works, illustrated ad design on two covers showing Train Crossing Bridge Over River Scene; in black with 1879, 3¢ green tied by Dayton, O. cds and target duplex, and in blue on yellow cover franked with 1¢ dark ultramarine tied by Dayton, O. cds and cork duplex, Very Fine, ex Foote. Estimate  $150 - 200. $0 (Image)